1. Field of the Invention
The present invention is related to the field of portable electronic devices such as cellular telephones, personal digital assistants (PDAs), players such as music players and game players, and the like, and more specifically to such devices that have an interface for manual entries by the user, and further features for reacting to user entries that were potentially inadvertent.
2. Description of the Related Art
Portable electronic devices such as cell phones, personal digital assistants, players, and the like are proliferating. Increasingly, people carry them on their persons for ease of use.
Many of these devices have interfaces for the user to make entries. A typical such interface is a keypad. For example, personal digital assistants have keypads for entering characters, along with other controls. For another example, cellular telephones (“cell phones” or “mobile telephones”) have keypads for dialing numbers, along with activation keys (that effectuate dialing and other functions). Other devices, such as iPOD-type players, have rotary interfaces, and so on.
A problem with such interfaces is that entries can be received inadvertently, from movements of the user. For example, when someone wears a cell phone on their person, they might later discover from the screen that certain buttons have been pressed inadvertently. They must then clear the inadvertent entries. It is even more of a problem when an activation key has been pressed inadvertently. For example, if it is a telephone, an inadvertently dialed number has been called.
Some solutions have been proposed for preventing inadvertently manual entries. For example, U.S. Pat. No. 4,859,100 provides a keypad with partitions between the keys. This can require more space to implement the keypad.
Others of these solutions have required users to take more steps. For example, a manual cover over a keypad can be opened. Or a soft lock feature can be implemented, where a password needs to be dialed first. Examples of these include U.S. Pat. Nos. 6,630,927, and 5,987,311.
Users can grow impatient when they are required to take more steps, and even neglect to take them. After all, taking more steps is just what they had to do to clear the inadvertent entries anyway.